With the development of optical communications technologies, requirements for optical switches with large capacity and high performance are increasingly growing in fields of optical switching, reconfigurable optical add/drop multiplexer (“ROADM”), online monitoring, and the like. However, currently, a key parameter, a return loss (“RL”) of a two-dimensional fiber array (“FA”) that is an important component in an optical switch can generally reach only 30 dB-40 dB, which causes relatively loud noise in a system and limits an application scope of the optical switch.
Currently, an RL of a two-dimensional FA is mainly improved by using the following method: An end face of the FA is horizontally polished, and matching fluid whose refractive index is consistent with a refractive index of a fiber is filled in between the FA and a to-be-combined component (such as an optical glass). An RL of a two-dimensional FA designed using this method may reach above 60 dB. However, it is difficult to obtain a material whose refractive index completely matches the refractive index of the fiber; in addition, efficient sealing of the matching fluid between the FA and the to-be-combined component is extremely difficult and is costly; therefore it is difficult to achieve large-scale production.